Tiger Woods, who started the day at even par, shot 65 to move into a tie for 17th at 205. His playing partner Luke Guthrie also shot 65. The twosome had the second tee time Saturday morning and took advantage of playing before the wind became a challenge.

"The wind really picked up for most of the round and it played tricky," said McIlroy, who teed off at 1:35 p.m. local time with a one-shot lead over playing partner Brendon de Jonge. "The wind was from a slightly different direction and made some holes play a lot easier but made a few of the holes, especially coming down the stretch, play very difficult."

McIlroy and De Jonge both birdied the first and third holes. Things got bad for De Jonge after that, as he bogeyed No. 4 and doubled No. 6. On the back nine he doubled No. 11, bogeyed 14 and closed with bogeys at 17 and 18 to shoot 76 and plummet to four under.

McIlroy bogeyed Nos. 6 and 7, but he did not let his round get out of control. In fact, his bogey at the par-three seventh gave him a lift.

His tee shot on the 237-yard hole bounced beyond the green and landed in a bunch of palmettos. He had to take a drop, and a penalty stroke, then hit a fabulous pitch from the vegetation 10 feet from the pin and sank the putt.

"I think a big point in my round was making a four on No. 7, making a really good bogey so I didn't go over par for the round," said McIlroy, 24, who had birdies on 12 and 16 to go with a bogey on 14.

"I stayed very patient. That was a key out there for me. I didn't panic."

Henley, 24, struggled on the front nine. He had a bogey on the second hole along with eight pars to go out in 36.

"I got off to a tough start," Henley said. "I felt like I was hitting the ball pretty decent the first couple of holes and didn't really get much out of it. But I hung tough and ended up having some things go my way on the back."

Those things included a birdie on 12. On the par-four 14th, Henley holed a 150-yard shot from the rough for an eagle.

A three-putt bogey on the par-three 15th stung, but he chipped in for birdie on the par-three 17th to get into the final pairing with McIlroy.

Henley said he is looking forward to the challenge of trying to overtake McIlroy, who has gone on to win all four tournaments when he's had the 54-hole lead since the 2011 Masters.

"I live for it," Henley said. "It doesn't get much better. I'm in the final group with a great player. I haven't played with him yet, but I've heard great things about him. I just hope I can go out there and play well."

Knox was as pleased with his 68 Saturday as he was with his 63 Friday.